### CVE-2021-25735: Validating Admission Webhook does not observe some previous fields

A security issue was discovered in kube-apiserver that could allow node
updates to bypass a Validating Admission Webhook. You are only affected
by this vulnerability if you run a Validating Admission Webhook for Nodes
that denies admission based at least partially on the old state of the
Node object.

Some of the details map precisely to the machine, but some do not.
This is because the compiler suite (see
<a href="https://9p.io/sys/doc/compiler.html">this description</a>)
needs no assembler pass in the usual pipeline.
Instead, the compiler operates on a kind of semi-abstract instruction set,
and instruction selection occurs partly after code generation.
The assembler works on the semi-abstract form, so

* Resolves a bug that prevented sending a multi-version custom resource to an admission webhook. ([#79495](https://github.com/kubernetes/kubernetes/pull/79495), [@liggitt](https://github.com/liggitt))
* Pass-through volume MountOptions to global mount (NodeStageVolume) on the node for CSI ([#80191](https://github.com/kubernetes/kubernetes/pull/80191), [@davidz627](https://github.com/davidz627))

* make node lease renew interval more heuristic based on node-status-update-frequency in kubelet ([#80173](https://github.com/kubernetes/kubernetes/pull/80173), [@gaorong](https://github.com/gaorong))
* Pass-through volume MountOptions to global mount (NodeStageVolume) on the node for CSI ([#80191](https://github.com/kubernetes/kubernetes/pull/80191), [@davidz627](https://github.com/davidz627))

- hyperkube: Use debian-hyperkube-base@v1.1.1...

    overrides the stored "Content-Encoding" header.
 *  Fix: Gracefully shut down the HTTP/2 connection before it exhausts the
    namespace of stream IDs (~536 million streams).
 *  Fix: Never pass a null `Route` to `Authenticator`. There was a bug where
    routes were omitted for eagerly-closed connections.

## Version 3.9.1

_2017-11-18_

* DELETE requests can now pass in their DeleteOptions as a query parameter or a body parameter, rather than just as a body parameter. ([#35806](https://github.com/kubernetes/kubernetes/pull/35806), [@bdbauer](https://github.com/bdbauer))

 * This URL references a share called <code>tmp</code> on the server
 * <code>angus</code> as user <code>miallen</code> who's password is
 * <code>mypass</code>.
 * </td></tr>
 * 
 * <tr><td width="20%">
 * <code>smb1://Administrator:P%40ss@msmith1/c/WINDOWS/Desktop/foo.txt</code></td><td>
 * A relativly sophisticated example that references a file

//
//	User-Agent:
//
//	    This is ignored from signing because signing this causes problems with generating pre-signed URLs
//	    (that are executed by other agents) or when customers pass requests through proxies, which may
//	    modify the user-agent.
//
//	Authorization:
//
//	    Is skipped for obvious reasons
var ignoredHeaders = map[string]bool{
	"Authorization": true,

- Kubeadm: during "join", don't re-add...